It would be great to see this Android app on F-Droid!
F-Droid is an Android app store specifically for free/libre open-source apps. It would be great if your app could be released there, as it is the number one for getting FLOSS Android apps for many people. F-Droid also builds all apps from source (optionally even reproducible), so downloads from there can be trusted.
BTW a release on F-Droid could also bring some (more) popularity (in case that is intended), as it will show up in the app (new apps are featured there).
Also checked the Guardian Project F-Droid repository, it's also not there.